Certificate Expiry Monitor vs crt.guru: Side-by-Side Comparison (2026)
Features, pricing, ratings, and pros & cons — compared head-to-head.
Certificate Expiry Monitor is a free certificate lifecycle management tool. crt.guru is a commercial certificate lifecycle management tool by crt.guru. Compare features, ratings, integrations, and community reviews side by side to find the best certificate lifecycle management fit for your security stack.
CST VerdictBased on our analysis of NIST CSF 2.0 coverage, core features, integrations, company size fit, here is our conclusion:
DevOps and platform teams running Kubernetes will get immediate value from Certificate Expiry Monitor because it catches certificate expirations before they cause outages, not after; the Prometheus integration means alerts land in the monitoring stack you already have rather than spawning another tool. The Docker-based deployment and native ingress discovery eliminate the manual certificate tracking spreadsheets that miss renewals across distributed environments. Skip this if you need centralized certificate lifecycle management with automated renewal workflows; Certificate Expiry Monitor is a monitor, not a manager, and works best paired with your existing provisioning process.
Security teams managing external-facing services across multiple regions need crt.guru for its multi-protocol scanning and Certificate Transparency monitoring, which catches unauthorized cert issuance before your domain gets impersonated. The tool covers ID.AM and DE.CM effectively by mapping your cert portfolio across Frankfurt, New York, and Amsterdam simultaneously, then alerting at granular intervals (30, 14, 7, 1 day) so you're not racing against expiry deadlines. Skip this if your organization has zero external TLS endpoints or relies on a managed WAF vendor that already owns cert lifecycle; crt.guru solves a specific problem rather than replacing internal PKI tooling.
